Flight MH370 transmitted handshake signals after vanishing

Handshake signals to an Inmarsat satellite from Malaysia Airlines flight MH370 seem to have been important in calculating the direction of flight of the airliner after it vanished from radar screens.

Analysis of the data from the Inmarsat satellite has resulted in the Prime Minister of Malaysia, Najib Razak, announcing earlier today that the missing Malaysia Airlines flight MH370 was lost and there were no survivors.

With the analysis, which also involved modelling of the messages passed across the Inmarsat network from flight MH370 and other known flights, the course of the aircraft after it had vanished was narrowed down to one of two routes, in northerly or southerly directions.

Prime Minister Razak revealed that new analysis of satellite information from Inmarsat, validated by the UK’s Air Accidents Investigation Branch, “have concluded that MH370 flew along the southern corridor, and that its last position was in the middle of the Indian Ocean, west of Perth”.

“This is a remote location, far from any possible landing sites. It is therefore with deep sadness and regret that I must inform you that, according to this new data, flight MH370 ended in the southern Indian Ocean,” said the Prime Minister of Malaysia.

It was analysis of the radio communications handshake signals, transmitted without manual intervention, to the Inmarsat satellite, which made it possible “to pass additional information to the relevant authorities regarding the likely direction of flight of MH370,” said an Inmarsat spokesman.

In radio communications “handshaking” refers to the automated signalling between two transceivers that is used by the system to establish the communications channel.

These “handshakes” are the standard radio signals mobile phones and satellite communications systems continually transmit to the satellite or basestation.

They can be used, by the network operator and the authorities, to pinpoint the position of the mobile phone or sat phone transmitter.

“This is first and foremost a tragedy for the passengers and their families and we extend our deepest sympathies to them all at this time,” said Chris McLaughlin, senior vice president, external affairs, at Inmarsat.

Flight MH370 disappeared after taking off on 8 March from Kuala Lumpur.